I’m just wondering how you get your Blender models to go behind things in composited pictures. For example, you go and take a picture of your dining room table. How do you make the character jump under it without jumping onto it?
You have to make a rough model of your dining room table in the scene with your character, and put its alpha = 0. When you render your character and the table at the same time, the table will cut off the parts of the character that pass under the table. The zero alpha of the table model will allow the real table to show when you composite the two images together.